* [jjo] add DIND support to contrib/

- add contrib/dind with ansible playbook to
  create "node" containers, and setup them to mimic
  host nodes as much as possible (using Ubuntu images),
  see contrib/dind/README.md

- nodes' /etc/hosts editing via `blockinfile` and
  `lineinfile` need `unsafe_writes: yes` because /etc/hosts
  are mounted by docker, and thus can't be handled atomically
  (modify copy + rename)

* dind-host role: set node container hostname on creation

* add "Resulting deployment" section with some CLI outputs

* typo

* selectable node_distro: debian, ubuntu

* some fixes for node_distro: ubuntu

* cpu optimization: add early `pkill -STOP agetty`

* typo

* add centos dind support ;)

* add kubespray-dind.yaml, support fedora

- add kubespray-dind.yaml (former custom.yaml at README.md)
- rework README.md as per above
- use some YAML power to share distros' commonality
- add fedora support

* create unique /etc/machine-id and other updates

- create unique /etc/machine-id in each docker node,
  used as seed for e.g. weave mac addresses

- with above, now netchecker 100% passes WoHooOO!
  🎉 🎉 🎉

- updated README.md output from (1.12.1, verified
  netcheck)

* minor typos

* fix centos node creation, needs earlier udevadm removal to avoid flaky facts, also verified netcheck Ok \o/

* add Q&D test-distros.sh, back to manual /etc/machine-id hack

* run-test-distros.sh cosmetics and minor fixes

* run-test-distros.sh: $rc fix and minor formatting changes

* run-test-distros.sh output cosmetics

* Update pre-install verify settings with network checks and etc.

* Remove upstream dns server check. It's bogus

- Local Volume StorageClass configuration is now manged by `local_volume_provisioner_storage_classes`, a list of maps that specifies local storage classes with `name` `host_dir` and `mount_dir` keys per entry
- Tasks and templates updated to loop through local volume storage classes
- Previous defaults for path/class names were not changed
- Fixed an issue where a `kubernetes/preinstall` was creating directories inconsistently with the `kubernetes-apps/external_provisioner/local_volume_provisioner` task

Fix wrong when condition that ends up with jinja error when the content of /etc/hosts contains parenthesis

* calico upgrade to v3

* update calico_rr version

* add missing file

* change contents of main.yml as it was left old version

* enable network policy by default

* remove unneeded task

* Fix kubelet calico settings

* fix when statement

* switch back to node-kubeconfig.yaml

Signed-off-by: Jeff Bornemann <jeff.bornemann@oracle.com>

we use FQDN as inventory_hostname

Hostname must be a valid DNS name, which is checked as https://github.com/kubernetes/apimachinery/blob/master/pkg/util/validation/validation.go#L115

The situation I have encountered is that my hostname contained underscore which is disallowed and apiserver refused to start.

Allow to use `ansible_become: true` (#2969)
And set it to `false` for `localhost` with an `host_var`

Use helm install or support in future

The number of pods on a given node is determined by the  --max-pods=k
directive. When the address space is exhausted, no more pods can be
scheduled even if from the --max-pods-perspective, the node still has
capacity.

The special case that a pod is scheduled and uses the node IP in the
host network namespace is too "soft" to derive a guarantee.

Comparing kubelet_max_pods with kube_network_node_prefix when given
allows to assert that pod limits match the CIDR address space.

* Move front-proxy-client certs back to kube mount

We want the same CA for all k8s certs

* Refactor vault to use a third party module

The module adds idempotency and reduces some of the repetitive
logic in the vault role

Requires ansible-modules-hashivault on ansible node and hvac
on the vault hosts themselves

Add upgrade test scenario
Remove bootstrap-os tags from tasks

* fix upgrade issues

* improve unseal logic

* specify ca and fix etcd check

* Fix initialization check

bump machine size

* sysctl file should be in defaults so that it can be overriden

* Change sysctl_file_path to be consistent with roles/kubernetes/preinstall/defaults/main.yml

This reverts commit 51f4e658.